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BACKGROUND: GDF-5 can induce the differentiation of human adipose-derived stem cells into chondrocyte-like cells, and chitosan/collagen scaffolds are widely used in cartilage tissue repair. OBJECTIVE: To repair rabbit articular cartilage defects by using rabbit autologous adipose-derived stem cells combined with chitosan/collagen scaffold and GDF-5 and to observe the repair effect. METHODS: Adipose-derived stem cells isolated from subcutaneous adipose tissues of Japanese rabbits were cultured, purified, amplified in vitro, and labeled with BrdU in vitro. The chitosan/collagen composite scaffold was prepared in a ratio of 1:3 using ultraviolet cross-linking method. Then labeled adipose-derived stem cells were seeded onto the scaffold and cultured to form complexes. A cylindrical defect (5 mm in diameter, 3 mm in depth) in the knee articular cartilage was surgically made in each rabbit, and these rabbit models were thereafter randomly divided into four groups. Composite group: adipose-derived stem cells+chitosan/collagen scaffold+GDF-5 complex implantation; stent group: simple implantation of chitosan/collagen scaffold; cell group: simple implantation of adipose-derived stem cells; and sham operation group: simple drilling without treatment. All the rabbits were intervened for 4, 8, and 12 weeks. Meanwhile, histological detection, type II collagen immunohistochemical staining and BrdU mmunofluorescence staining were performed. RESULTS AND CONCLUSION: (1) At 12 weeks after surgery, the cylindrical defect of the composite group was completely filled with the same milky white transparent substance as the surrounding normal cartilage, and the cartilage defect area was replaced by differentiated hyaline cartilage. Of all the groups, Wakitani score was the lowest in the composite group (P < 0.01). (2) Type II collagen immunohistochemical staining and BrdU immunofluorescence staining: in the composite group, the type II collagen stained cytoplasm in the repaired area was detected by immunohistochemical staining at 4, 8, and 12 weeks after surgery. The expression of BrdU in the new tissues of the repaired area was positive. These results confirm that autologous adipose-derived stem cells+chitosan/collagen scaffold+GDF-5 complex grafting has a good effect on the repair of rabbit knee cartilage defects. Subject headings: Stem Cells; Tissue Engineering; Chitosan; Stents Funding: the Youth Foundation of Shenyang Medical College, No. 20142050; the Fund of Shenyang Health and Family Planning Commission [ABSTRACT FROM AUTHOR]